Efficacy and safety of PD-1/PD-L1 inhibitors combined with anti-angiogenic therapy for the unresectable hepatocellular carcinoma and the benefit for hepatitis B virus etiology subgroup: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND: Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death, worldwide. The predominant causative factor for HCC is hepatitis B virus (HBV) infection. We conducted a meta-analysis to estimate the efficacy and safety of PD-1/PD-L1 inhibitors combined with anti-angiogenic therapy for the first-line treatment of the unresectable HCC and to evaluate the benefits of different geographic regions and etiology stratifications. METHODS: Randomized clinical trials published up to 12th November 2022 were searched by online databases. Moreover, effects of hazard ratio (HR) for overall survival (OS) and progression-free survival (PFS) were extracted from included studies. Pooled odds ratio (OR) and 95% CI for objective response rate (ORR), disease control rate (DCR), and treatment-related adverse events (TRAEs) were calculated. RESULTS: A total of 3057 patients from five phase III randomized clinical trials were collected and reviewed for this meta-analysis. The pooled HR of OS (HR = 0.71; 95% CI: 0.60–0.85) and PFS (HR = 0.64; 95% CI: 0.53–0.77) demonstrated significantly better benefit in PD-1/PD-L1 inhibitors combination group than targeted monotherapy to treat unresectable HCC. In addition, combination therapy showed better ORR and DCR, with ORs of 3.29 (95% CI: 1.92–5.62) and 1.88 (95% CI: 1.35–2.61), respectively. The subgroup analysis indicated that PD-1/PD-L1 inhibitors combination therapy was significantly superior to anti-angiogenic monotherapy for HBV-related HCC in terms of OS (HR = 0.64; 95% CI: 0.55–0.74) and PFS (HR = 0.53; 95% CI:0.47–0.59), while there was no significant difference in patients with HCV (OS, HR = 0.81, p = 0.1) or non-viral (OS, HR = 0.91, p = 0.37; PFS, HR = 0.77, p = 0.05). CONCLUSIONS: Meta-analysis revealed for the first-time that PD-1/PD-L1 inhibitors combination therapy for unresectable HCC was associated with better clinical outcomes than anti-angiogenic monotherapy, especially for HBV infection and Asian population. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12885-023-10960-w.